Suspension for cone loud-speakers



p 1929: 1.. SHAPIRQ 1,707,283.

SUSPENSION FOR CONE LOUD SPEAKERS Filed Aug. v, 1926 INVENTOR WITN E55 LAZAHUS SHA FIFO a? I k Patented Apr. 2, 1929. l

* UNITED STATES PATENT OFFICE.

LAZARUS SHAPIRO, OF NEW YORK, N. Y., ASSIGNOR TO FREED-EISEMANN RADIO. CORPORATION, OF BROOKLYN, NEW YORK, A CORPORATION OF ,NEW YORK.

SUSPENSION FOR CONE LOUD'-SPEAKEBS.

Application filed August 7, 1926. Serial No. 127,864.

The invention is illustrated in the accompanying drawing which represents a longitudinal vertical section thru the cone and its suspension. i

In loud speaking devices in which a cone is employed as a sound radiator it 18 desirable to give. the cone as much freedom of motion as possible so that it may oscillate as freely as possible, when actuated at 1ts apex in the direction of the cone axis by the open ating rod connected to the source of sound energy, such as for instance an oscillat ngarmature thru which electrical audio frequency oscillations are electromagnetically converted into mechanical oscillations.

Many types of such devices are known in the art and their detailed illustration has therefore been omitted in the present specification.

The novel idea involved in the cone sus pension is a support attached to the cone intermediate its apex and its periphery which will permit the cone, due to the yielding nature of the support to substantially 2 freely oscillate when actuated by the device hereinbefore referred to,

In the drawing which illustrates the principle, 1 represents a supporting base, the upward extending curved arm of which carries a ring 2, to the rear side of which the. electromagnetic actuating mechanism 3 is attached by means of a suitable number of horizontal arms4. Audio frequency current is supplied to the mechanism by means of cord 121 From the actuating mechanism 3 extends the operating rod 6 which passes thru the central-axis of ring 2 and which is attached at its free end to the apex of cone 5 by means of achuck 7 or any suitable means known in the art for that purpose. Cone 5 may be made of any suitablethin sheet material such as fairly stifl paper, and in order to apply a certain amount of stiffnes's to its periphery it is provided at that portion witha double crimp as shown at 8 rghich-is sufiicient to keep the periphery in s ape.

In order. to support this cone so that its weight may not rest upon the operating rod 6, I provide the following means. To the front end of ring 2 is attached a disk 9 of suitable flexible sheet material such as for instance fairly stifi' paper, this disk 9 being attached to ring 2 by means of a clamping ring 10.. I The central portion of disk 9 withand the outside air.

in ring 2 is cut out so as to permit free communication between the chan iber, form-v ed by the disk and the central cone portion,

This disk is fixed to thecone, for instance by gluing its edge 13 to the cone. lVhcn this disk is mounted on the cone and before it isv attached to ring 2 y it is -in a straight plane. After the cone chuck has been slid over-tho operating rod 6 and after the clamping ring 10 has been tightened and thus the disk been attached to ring 2, the apex is slightly pulled away from disk 2 and the chuck is then tightened on the operating rod. This slightly dishes 'disk 9, thereby putting it under sufficient tension to make it fairly rigid so as to enable it to form the support for the cone without permitting the weight of the cone to bear on the-operating rod 6. Yet. due to the only very slight dishing disk 9 is still able to permit the cone to substantially freely oscillate in the direction of its" axis.

In other words, the periphery of disk 8 where it joins the loud speaker cone 5 does not form in any way a circular pivotal line on which the cone would oscillate. Practi cal experience shows that the peripheral.

portion of disk 9 follows the oscillations of the cone substantially in the direction of the two arrows, in other words, in the direction of the cone axis when the electromagnetic unit operates rod 6. In the draw ing the dished character of disk 9 is slightly exaggerated; it may be regulated when mounting the loud speaker cone such that it is just suflicient to give the cone the desired support without interfering to any appreciable extent with the, free cone oscil- Y lations. 1

Instead of slightly dishing disk 9 in the manner described above,.I may instead give the disk a dished shape, by any suitable means known in the art,rpreliminary to -mounting it, so that it becomes unnecessary to pull out the cone apex before fixing it to the operating rod as aforementioned, thus avoiding biasing mechanical stresses on the actuating mechanism 3.

While I have in particular referred in the foregoing to an electromagneticactuating mechanism for operating the cone, it is understood that the character'of this mechanism is immaterial to the function of the present improvement, and any other actuatingmechanism which will suitably oscillate the cone thru the operating rod 6 may be substituted without limiting the scope of my invention. w

I claim a 1. A cone loud speaker of the character described comprising in combination a sound radiating cone actuated at its apex,

a supporting disk of suitable'flexible sheet material, rigidly held near its central portion and attached at its periphery to said cone intermediate the cone apex and the cone periphery, an operating rod extending in the direction of the cone axis and attached to the cone apex for oscillating said cone, said disk being held under slight tension in dished shape by the operating rod to impart suiiicient rigidity to said disk for holding the cone in position, said disk permitting the cone to substantially freely oscillate in the direction of the cone axis, and means for actuating saidoperating rod.

2. A cone loud speaker of the character described eomprising'in combination a sound radiating cone actuated at itsapex, a supporting disk-shaped annulus of suitable sheet material having a diameter considerably smaller than the cone diameter and being fixed at its outer periphery to said cone (.OIIOGIliBIlCiIl with the cone axis, a supporting rbase having a ring and means for rigidly clamping the inner rim of said annulus to said ring, an actuating device for said cone fixed to said ring and having an operating rod extending substantially in line with the cone axis and being attached at its free end to the cone apex for oscillating said cone, said annulus being held under slight tension in dished shape by said operating rod to impart snfiicient rigidity to the annulus for holding the cone "in position, said annulus permitting the cone to substantially freely oscillate in the direction of the cone axis.

LAZARUS SHAPIRO. 

